point
How do I draw a point using Core Graphics?
CGContextFillRect(context, CGRectMake(x,y,1,1));
Checking if a point is inside a polygon
I would suggest using the Path class from matplotlib import matplotlib.path as mplPath import numpy as np poly = [190, 50, 500, 310] bbPath = mplPath.Path(np.array([[poly[0], poly[1]], [poly[1], poly[2]], [poly[2], poly[3]], [poly[3], poly[0]]])) bbPath.contains_point((200, 100)) (There is also a contains_points function if you want to test for multiple points)
See if lat / long falls within a polygon using mysql
MySQL as of v5.1 only supports operations on the minimum bounding rectangles (MBR). While there is a “Contains” function which would do what you need, it is not fully implemented and falls back to using MBRContains From the relevant manual page Currently, MySQL does not implement these functions according to the specification. Those that are … Read more
Find if point lies on line segment
Find the distance of point P from both the line end points A, B. If AB = AP + PB, then P lies on the line segment AB. AB = sqrt((x2-x1)*(x2-x1)+(y2-y1)*(y2-y1)+(z2-z1)*(z2-z1)); AP = sqrt((x-x1)*(x-x1)+(y-y1)*(y-y1)+(z-z1)*(z-z1)); PB = sqrt((x2-x)*(x2-x)+(y2-y)*(y2-y)+(z2-z)*(z2-z)); if(AB == AP + PB) return true;
Distance between point and a line (from two points)
Try using the norm function from numpy.linalg d = norm(np.cross(p2-p1, p1-p3))/norm(p2-p1)
Java: Calculating the angle between two points in degrees
you could add the following: public float getAngle(Point target) { float angle = (float) Math.toDegrees(Math.atan2(target.y – y, target.x – x)); if(angle < 0){ angle += 360; } return angle; } by the way, why do you want to not use a double here?
Quadratic Bézier Curve: Calculate Points
Use the quadratic Bézier formula, found, for instance, on the Wikipedia page for Bézier Curves: In pseudo-code, that’s t = 0.5; // given example value x = (1 – t) * (1 – t) * p[0].x + 2 * (1 – t) * t * p[1].x + t * t * p[2].x; y = (1 … Read more
Why is the ELF execution entry point virtual address of the form 0x80xxxxx and not zero 0x0?
As Mads pointed out, in order to catch most accesses through null pointers, Unix-like systems tend to make the page at address zero “unmapped”. Thus, accesses immediately trigger a CPU exception, in other words a segfault. This is quite better than letting the application go rogue. The exception vector table, however, can be at any … Read more